Let's roll up our sleeves and solve this. We have 70 and we're going to multiply it by 23, essentially adding 70 to itself 23 times.
Step 1: 0 + 70 = 70
Step 2: 70 + 70 = 140
Step 3: 140 + 70 = 210
Step 4: 210 + 70 = 280
Step 5: 280 + 70 = 350
Step 6: 350 + 70 = 420
Step 7: 420 + 70 = 490
Step 8: 490 + 70 = 560
Step 9: 560 + 70 = 630
Step 10: 630 + 70 = 700
Step 11: 700 + 70 = 770
Step 12: 770 + 70 = 840
Step 13: 840 + 70 = 910
Step 14: 910 + 70 = 980
Step 15: 980 + 70 = 1050
Step 16: 1050 + 70 = 1120
Step 17: 1120 + 70 = 1190
Step 18: 1190 + 70 = 1260
Step 19: 1260 + 70 = 1330
Step 20: 1330 + 70 = 1400
Step 21: 1400 + 70 = 1470
Step 22: 1470 + 70 = 1540
Step 23: 1540 + 70 = 1610

So, 70*23 = 1610